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प्रश्न
Give reasons: Transition metals show variable oxidation states.
Account for the following :
Transition metals show variable oxidation states.
उत्तर १
The transition metals have their valence electrons in (n-1)d and ns orbitals. Since, there is very little energy difference between these orbitals, both energy levels can be used for bond formation. Thus, transition elements exhibit variable oxidation states.
उत्तर २
The variable oxidation states of transition elements are due to the participation of ns and (n−1)d-electrons in bonding. Lower oxidation state is exhibited when the ns-electrons take part in bonding. Higher oxidation states are exhibited when the (n − 1)d-electrons take part in bonding.
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